Cutting

ABSTRACT

CUTTING DIE COMPRISNG FLAT TABLE CUTTING EDGE WITH CURVILLINEAR SIDES EXTENDING UPWARDLY OF A THIN, FLEXIBLE BASE AND METHODS FOR PRODUCING AN DUTILIZING SAME.

W. A. SIMSON Nov. 9, 1971 CUTTING 2 Shoots-Shoat 1 Filed Nov. 6. 1968 ATTORNEYS Nov. 9, 1971 w. A. SIMSON 3,618,438

CUTTING Filed Nov. 6, 1968 2 Sheets-Sheet 2 FIGS INVENTOR. WALTER A. SIMSON Z WW ATTORNEYS United States Patent 3,618,438 CUTTING Walter A. Simson, New York, N.Y. (230 Beverly Road, Scarsdale, N.Y. 10538) Filed NOV. 6, 1968, Ser. No. 773,816 Int. Cl. B2611 1/56 US. Cl. 83-117 ABSTRACT OF THE DISCLOSURE Cutting die comprising fiat table cutting edge with curvilinear sides extending upwardly of a thin, flexible base and methods for producing and utilizing same.

This invention relates generally to cutting, and, more particularly, to the cutting of paper during passage through a printing press and to cutting dies therefor.

A primary object of the present invention is the provision of novel and improved methods and apparatus for cutting, particularly of paper during passage through a cylinder printing press.

Another primary object of the present invention, in addition to the foregoing object, is the provision of novel and improved cutting dies, particularly for mounting in a cylinder printing press for cutting paper during passage therethrough.

Yet another primary object of the present invention, in addition to each of the foregoing objects, is the provision of novel and improved cutting dies, particularly for utilization with cylinder printing presses, capable of 17 Claims producing substantially any desired configuration of cut at high speeds.

A still further primary object of the present invention, in addition to each of the foregoing objects, is the provision of novel and improved web offset printing presses adapted to provide cutting of a paper web during passage therethrough.

Yet still further, it is another primary object of the present invention, in addition to each of the foregoing objects, to provide cutting during passage of a web of paper through a web offset printing press.

Still another and further primary object of the present invention, in addition to each of the foregoing objects, is the provision of novel and improved methods of manufacturing cutting dies.

Yet still further, in addition to each of the foregoing, it is another primary object of the present invention to provide novel and improved cutting dies and methods of manufacture thereof.

Still further, in addition to each of the foregoing objects, it is still another primary object of the present invention to provide novel and improved cutting dies for substantially any desired contour which may be utilized in conjunction with, for example, web offset printing presses for cutting of the web during passage therethrough which may be produced at a nominal cost.

Another and yet still further primary object of the present invention, in addition to each of the foregoing objects, is the provision of novel and improved cutting dies which may be produced inexpensively, which cut effectively, and which have a long life.

Yet still further, it is another primary object of the present invention, in addition to each of the foregoing objects, to provide novel and improved cutting dies which may be readily, easily and quickly fabricated to a desired contour utilizing only equipment which is generally available to the printing industry.

It is still another primary object of the present invention, in addition to each of the foregoing objects, to provide methods and apparatus for cutting a sheet-like material, such as paper, during passage thereof through an offset printing press, such as a web offset printing press, to enable cutting to be accomplished in conjunction with offset printing at high speeds during a single pass.

Yet still another and further primary object of the present invention, in addition to each of the foregoing objects, is to provide methods and apparatus for adapting a web offset printing press to enable the printing press to provide inked imagery and cutouts, cuts, perforations, slots, slits, scoring, embossing and other multi-dimensional effects on a web of material passed therethrough during a single operation.

Another and still further primary object of the present invention, in addition to each of the foregoing objects, is to provide such methods and apparatus which enable the printing press to be set-up for a specific run in a minimum of time by relatively unskilled technicians.

It is also a primary object of the present invention, in addition to each of the foregoing objects, to provide offset printing presses adapted to provide both inked imagery and cutouts, cuts, perforations, slots, slits, scoring, embossing and other multi-dimensional effects of substantially any desired configuration to sheet-like material in a single operation, at high speeds, and at a minimum of cost.

The invention resides in the combination, construction, arrangement and disposition of the various component parts and elements incorporated in improved apparatus constructed in accordance with the principles of this invention, methods of making and of utilizing such apparatus and the products produced thereby. The present invention will be better understood and objects and important features other than those specifically enumerated above will become apparent when consideration is given to the following details and description, which when taken in conjunction with the annexed drawings describes, discloses, illustrates and shows certain preferred embodiments or modifications of the present invention and what is presently considered and believed to be the best mode of practicing the principles thereof. Other embodiments or modifications may be suggested to those having the benefit of the teachings herein, and such other embodiments or modifications are intended to be reserved especially as they fall within the scope and spirit of the subjoined claims.

lIn the drawing:

FIG. 1 is an isometric illustration of a cutting die constructed in accordance with the principles of the present invention;

FIG. 2 is an elevational cross-sectional partial view taken along line 2-2 of FIG. 1;

FIG. 3 is an isometric schematic illustration of a cylinder printing press having the cutting die of the preceding figures operatively associated therewith;

FIG. 4 is a cross-sectional, elevational, partial View similar to FIG. 2 of another cutting die fabricated in accordance with the principles of this invention; and

FIG. is a photo-micrograph of a cross-section taken through a cutting die fabricated in accordance with the present invention magnified one hundred times.

In accordance with the present invention, a sheet of fully hardened, high carbon steel is chemically milled or etched, for example, utilizing photofabrication techniques to produce a cutting die comprising a flat table cutting edge having generally curvilinear sides extending generally upwardly from an integral, flexible base, enabling the die to be readily bent to conform to and be adhesively secured on a cylinder printing press to cut paper during passage therethrough.

Accordingly, and with particular reference now to FIGS. 1 and 2, there is shown and illustrated a cutting die designated generally by the reference character which may be fabricated as by chemical milling utilizing photofabrication techniques from a solid sheet of fully hardened, high carbon steel, such as a sheet 12 of razor steel as indicated by the phantom lines in FIGS. 1 and 2. For example, the sheet 12 may be coated with a photosensitive resist, in a well known manner, as by spraying, dipping, rollercoating, or the like, followed by exposure thereof to a photographic mask or negative, development and removal of the unexposed resist layer in accordance with well known techniques to provide a resist mask 14 on the surface of the sheet 12'. Then, in accordance with well known techniques, the sheet 12 is etched, as by bath or spray etching equipment so as to undercut the resist mask 14 and define the finished die 10 as comprising a relatively thin backing layer 16 having cutting edge means 18 extending generally upwardly therefrom and defined, in turn, by a generally fiat table edge 20 and generally concave or curvilinear sides 22 extending from the table edge 20 to the upper surface 24 of the base portion 16.

As is readily obvious, the resist mask 14 may be of substantially greater width than the desired finished width of the flat table edge 20 and, assuming a 1:1 etch factor, i.e., that the etching is conducted in such a manner that the material is etched equally in all directions, then the width of the resist mask should be equal to twice the desired depth of etch plus the desired width of the flat table edge and the thickness of the base portion 16 may be selected or chosen so as to provide a sufiicient amount of resiliency to the die 10 to enable it to be readily and easily bent to conform to a printing press cylinder, as will be hereinafter described, and be readily and easily secured thereto, as by means of double faced adhesive sheet material, while being yet of sufficient thickness to maintain structural integrity. It is not necessary, however, that the base thickness be defined solely by the original thickness of the sheet 12 and the depth of the etch defining the cutting edge 18. If desired, a thicker sheet of material may be utilized and the base thickness re-defined, subsequent to formation of the cutting edge by removal of metal from the backside of the sheet of material, as by a uniform etching or mechanical metal remover therefrom.

The cutting edge 18 may, accordingly, be of substantially any desired configuration, i.e., configured or contoured to provide round cuts, oblong cuts, straight cuts, combination cuts, continuous cuts, interrupted or perforated cuts, and the like. Yet further, the desired contour or configuration would not substantially affect the cost, in either time, labor or materials required to produce the finished die. Moreover, since the chemical etching proceeds generally across the entire surface of the sheet, the amount of labor and time required is substantially the same independent of the overall size of the die produced and, a plurality of dies may even be produced simultaneously at substantially the same cost as would be required for a single die. Yet further, since the major cost of producing cutting dies in accordance with the present invention is generally the cost of producing the original art work which may, for example, be substantially larger, such as ten times larger, than the desired finished die which would then be reproduced and reduced photographically,

4 multiple dies may be readily, easily and inexpensively produced in accordance with the present invention. Large sheets of die elements designed to produce identical, similar or entirely unrelated and different contours may be inexpensively produced in accordance with the present invention for subsequent separation into individual or smaller compound die sheets.

If desired, the resist mask may be applied directly, i.e., as by means of a ruling pen, by well known cutting and stripping techniques, or the like, rather than being applied and defined by photofabrication techniques as hereinabove set forth, although such dies may not be as uniform, accurate and long-lived.

Cutting dies fabricated in accordance with the present invention may be utilized on substantially any type of press, and are particularly adapted to be utilized on printing presses for cutting of paper and may be utilized to cut the paper simultaneously with printing thereon. The cutting dies of the present invention are equally suitable for use on both flat bed and rotary or cylinder presses and are of particular utility when utilized in conjunction with Web offset rotary printing presses to enable a web of paper to be printed on one or both sides in a multiplicity of colors and simultaneously provided with cutouts or severed portions.

Web offset printing presses may be of several different types. Referring now to FIG. 3 of the drawing, there is shown and illustrated a press unit with an impression cylinder, the press unit being designated generally by the reference character 26. The press unit 26 comprises blanket cylinder 28 rotationally carried on a shaft 30 and provided with a soft and resilient blanket 32 extending generally circumferentially thereabout for receiving an ink image from one or more plate cylinders (not shown) and transferring the ink image received therefrom to the web of paper or other sheet-like material 34 which is squeezed thereagainst by means of an impression cylinder 36; the sheet-like material 34 passing therebetween. The impression cylinder 36 is similarly rotationally carried on a shaft 38. The impression cylinder 36 is conventionally provided with a hard surface and squeezes the web of sheet-like material 34 against the blanket 32.

The other basic type of web offset printing press is the perfecting press unit. The perfecting press unit is similar to the press unit 26 but the cylinder 36, rather than being a hard surfaced impression cylinder comprises a blanket cylinder associated with a second plate cylinder and ink feed rolls (not shown) to enable ink images to be applied to both sides of the web of sheet-like material 34 simultaneously. While the blanket cylinders of either basic press type are capable of applying multi-color ink images to the web of sheet-like material 34, the individual press units are conventionally associated in series so that the web of material 34 is sequentially fed to each press unit of the series so that each blanket cylinder only applies to a single color ink to the web of sheet-like material.

As heretofore pointed out, this invention is equally applicable to both basic types of web offset printing presses, i.e., to web offset printing presses having impression cylinders, to perfecting type presses, to drum type presses, or the like, as well as to any other printing presses, such as sheet fed rotary or fiat-bed presses.

With further reference to FIG. 3, the blanket cylinder 28 conventionally comprises a hard material fabricated, for example, of cast iron or steel. The blanket 32 may comprise, as heretofore pointed out, a relatively soft and resilient material such as rubber. The cutting die 10 may be secured with the impression cylinder 36 in any desired manner with the cutting edge 18 extending generally radially outwardly thereof so as to pierce the web of material 34 by cooperation with the blanket 32; the blanket 32 functioning as a resilient backup or female die member therefor. If it is desired to transfer an ink image from the blanket 32 to the Web of sheet-like material 34 during the cutting operation, i.e., on that particular press unit, then it is necessary that constant pressure be applied to all parts of the web of sheet-like material or paper 34 in contact with the blanket member 32 by the impression cylinder 36. If it is not desired to transfer an ink image to the web of sheet-like material or paper 34 during the cutting operation, i.e., with that particular press unit, then the impression cylinder 36 may be spaced from the surface of the blanket member 32 a distance sufficient that only the raised or cutting portion 18 of the die member will be pressed into the blanket member 32 and the base portion 16 of the die member 10 will not provide any embossing, cutting or other effect on the web of paper or sheet-like material 34.

As heretofore pointed out, if it is desired to transfer an ink image from the blanket member 32 to the web of paper or sheet-like material 34, then it is necessary to provide pressure against the web of paper or sheet-like material 34 at all points of contact with the blanket member 32. Accordingly, a masking layer 40 may be provided on the surface of the impression cylinder 36 adjacent the base portion 16 of the die member 10 to effectively build up the impression cylinder 36 to the thickness of the die member base portion 16. In other words, the upper surface of the masking layer 40 may form a continuation of the upper surface 24 of the die member base portion 16. With such a masking layer 40 so positioned, the base portion 16 of the die member 10 will be enclosed by the masking layer 40 and will therefore not present any edges capable of embossing, cutting or otherwise affecting the Web of paper or other sheet-like material 34.

As heretofore pointed out, the die member 10 may be positioned on the impression cylinder 36 in any desired manner, as by means of an adhesive, and adhesive tape, or the like. For example, a layer of double-faced adhesive tape 42 may be secured to the surface of the impression cylinder 36 and the masking layer 40 being secured on the upper surface of the double-faced adhesive layer 42. The masking layer 40 may comprise any desired material, and it has been found that a relatively tough plastic material is especially suitable. For example, a polyester film material such as a film material comprising polymers of ethylene terephthalate has been successfully utilized.

The proper positioning of the die member 10 may be determined by operating the press unit without passing the web of paper or other sheet-like material 34 therethrough to thereby transfer an ink image from the blanket member 32 directly to the masking layer 40, and then cutting an aperture 44 at the appropriate location as indicated by the ink image entirely therethrough to define a recess with the upper adhesive surface of the doublefaced adhesive layer 42 being exposed at the bottom thereof. The aperture recess 44 should be configured substantially complementary to the periphery of the base portion 16 of the die member 10 so that the die member 10 may be inserted therein and secured with the impression cylinder 36 by the upper adhesive surface of the doublefaced adhesive 42.

Accordingly, if the thickness of the die member base portion 16 and the masking layer 40 are chosen to be substantially the same, the raised portion or cutting edge 18 of the die member 10 will project generally upwardly from a substantially smooth and continuous surface defined by the upper surface 24 of the die member base portion 16 and the outer surface of the masking layer 40.

While the diameters of the impression cylinder 36 and the blanket cylinder 28 should be substantially the same, it has been found that any difference in the effective diameters of the cylinders produced by the masking layer 40 is negligible.

As heretofore pointed out, the present invention is equally suited for use with perfecting type presses. However, since both cylinders of a perfecting type press are generally covered with blanket members and a blanket member does not give sufiicient support beneath a cutting die, the blanket should be removed from the cylinder upon which the cutting die is to be mounted and the cylinder built up to proper diameter utilizing, for example, a blank printing plate and paper, or the like, between the printing plate and cylinder core to define the structural equivalent of the impression cylinder 36. With either type of press or press unit, the function of the blanket 32 as an ink transfer or offset member is not adversely affected and ink imagery can be transferred to the web of paper or sheet-like material 34 simultaneously with cutting. Accordingly, the web of sheet-like material or paper 34 may, in a single pass, be provided with ink images in a multiple of colors and on one or both sides thereof while being simultaneously cut with the cutting die 10.

The die 10 heretofore described and illustrated is for completely severing an enclosed area of the web of material 34. As heretofore pointed out, however, dies fabricated in accordance with the present invention may be utilized not only to produce cutouts, as illustrated, but may also be utilized to provide cuts of straight, curvilinear, or complex configuration, slits, slots, perforations or interrupted cuts, edge cuts, or the like. Moreover, and particularly when utilized in conjunction with Web offset printing presses, it is preferable that no separation of the cut portion of the paper from the main web occur within the printing press or at the printing station since the presence of paper cutting within the press itself may produce substantial difiiculties. Hence, when dies such as the die 10 illustrated are desired to provide cutouts within the web of material 34, is is preferable that the die not be entirely complete in circumscribing the cutout area but, rather, that nips or bridges of small dimensional extent be provided to retain the cutout secured with the web of material 34 and to provide for stripping at a later station or entirely off the press, as at the sheet separating or severing location. Yet further, supplemental resilient ejecting means may be provided within the confines of the die edges to assure that the web of material will be ejected from the die and to prevent any stock buildup within the confines of the die.

Accordingly, and with reference now to FIG. 4, there is shown and illustrated another cutting die substantially similar to the die heretofore described. In the ensuing description, only those details wherein the die shown and illustrated in FIG. 4 differs from the die hereinbefore described will be described in detail. Moreover, similar reference characters will be utilized as utilized hereinbefore, the reference characters being primed. Hence, the die illustrated in FIG. 4 is generally designated by the reference character 10 and it is to be expressly understood that those details which are not hereinafter described are substantially identical to the corresponding details of the die 110.

The die 10' is provided with an aperture 46 extending through the base portion 16' generally between the cutting edges 18'. An elastomeric plug 48' having an upper surface 50' extending above the surface 24' of the base portion 16' is disposed within the aperture 46' to resiliently clear any scrap or cuttings out of the space between the cutting edges 18'. To assure that the cut portion of the working material will be properly ejected from the die 10, the upper surface 50' of the elastomeric plug 48' may project higher than or above the table edge 20'. A thin backup plate 52' may also be provided bonded to the die member base portion 16' and, preferably, to the elastomeric plug 48'.

Hence, the material cut by the cutting edge 18' will tend to be cleared from the cutting die 10' by the resilience of the elastomeric plug 48'.

As heretofore pointed out, cutting dies fabricated in accordance with the present invention must have the cutting edges 18 extending above the base portion a distance sufficient to sever the paper or other material to be cut. Further, the base portion 16 should be of such a thickness as to be sufficiently flexible to be capable of being wrapped around the curved surface of the impression cylinder 26 and readily and easily secured thereto, as by means of the double-faced adhesive 42. Accordingly, it has been found that a cutting die fabricated of fully hardened high carbon steel having a base thickness in the approximate range of .005 to .010 possess sufficient flexibility to enable ready and easy conformance to the surface of the impression cylinder while yet having suflicient strength to maintain structural integrity. Yet further, with such a base thickness, the die may be readily and easliy trimmed to a desired contour.

Yet further, it has been found that a cutting edge height within the approximate range of .015 to .025" will satisfactorily cut 60 pound paper stock and that cutting edges having a flat table width of approximately .001 to .005" provides satisfactory results. The thinner cutting edges provide slightly smoother cuts but, when it is attempted to make the cutting edge substantially less than approximately .001" width, the width edge lacks sufficient me chanical strength and, additionally, it becomes increasingly difficult to form a narrower flat table edge without forming a sharp edge which, because of the geometries involved, tends to cause wide variations in cutting edge height. Such wide variations in height occur because the sides of the cutting edge are at such a narrow angle relative to one another that a very slight difference in width of the cutting edge results in a great or highly mag nified difference in height, once the table edge is entirely eliminated. Moreover, the arcuate sides 22 of the cutting edge 18 produce a cutting edge which, as it readily seen from the drawing, is of substantially uniform thickness for a slight difference down from the table edge 20, enabling the cutting edge to remain sufiiciently sharp over a long useful life while thereafter, the width of the cutting edge 18 increases rapidly, providing great strength thereto.

While as heretofore described, the cutting edge 18 is disclosed as being produced by first defining the cutting edge pattern through photochemical means, i.e., through the use of a photosensitive resist followed by actual formation of the cutting edge by chemical activity, more particularly, etching or chemical milling; yet, it is believed readily obvious that similar cutting edges may be formed by other manufacturing processes, including hand application of resist, printed application of resist or cutting away of a resist layer, all techniques that are well known in other arts, such as the printed circuit fabrication arts, and removal of the excess metal by processes other than chemical etching or chemical milling, such as by means of electrodischarge machining, engraving, or the like. It is believed readily apparent, however, that whatever process is utilized to fabricate the cutting edges, it is preferably one which is capable of being utilized on fully hardened metal, such as the aforementioned chemical milling or electrodischarge machining.

Yet further, substantially any desired cutting edge pattern, including straight, curvilinear, compound, continuous and discontinuous, such as interrupted and perforating cutting edges and dies wherein the edges do not cut or completely cut the paper, as for scoring and em bossing, using the lower table heights and/or rounded edges of the flat table may be produced in accordance with the present invention. Cutting dies comprising a plurality of separate or separable cutting or forming portions may also be produced, as heretofore pointed out.

While the invention has been described, disclosed, illustrated and shown in terms of certain preferred embodiments or modifications which it has assumed in practice, the scope of the invention should not be deemed to be limited by the precise embodiments or modifications herein described, disclosed, illustrated or shown, such other embodiments or modifications as may be suggested to those having the benefit of the teachings herein being intended to be reserved especially as they fall within the scope and breadth of the subjoined claims.

What is claimed is:

1. A cutting die and a cooperating resilient blanket member for use in an offset printing press to sever paper passed therebetween said cutting die comprising an homogenous piece of hardened sheet metal having a major portion of the surface thereof recessed, as by chemical milling, so that the unrecessed portion defines a thin cutting edge having a substantially flat upper surface less than approximately .005 inch width projecting upwardly of a plate-like base portion so that passing such paper between said die and such blanket member forms a uniform and clean single cut without embossing.

2. Cutting die defined in claim 1 comprising fully hardened, high carbon steel and wherein said base portion is sufiiciently thin so as to exhibit sufficient flexibility to enable bending to conform with a cylinder of a web offset printing press and securement thereto by pressure sensitive adhesive.

3. Cutting die defined in claim 2 comprising 1075 carbon steel.

4. Cutting die defined in claim 1 wherein the width of said flat cutting edge is greater than approximately .001 inch.

5. Cutting die defined in claim 1 wherein said fiat table cutting edge is within the approximate range of .001-.005 inch width.

6. Cutting die defined in claim 1 wherein said cutting edge projects less than approximately .025 inch from said base portion.

7. Cutting die defined in claim 1 wherein said cutting edge projects between approximately .015-.025 inch from said base portion.

8. Cutting die defined in claim 2 wherein said base portion is of more than approximately .005 inch thickness.

9. Cutting die defined in claim 2 wherein said base portion is of less than approximately .010 inch thickness.

10. Cutting die defined in claim 2 wherein said base portion is between approximately .005 and .010 inch thickness.

11. Cutting die couple comprising, in combination, a resilient blanket member of an offset printing press and a uniform and homogenous sheet of fully hardened high carbon steel having portions chemically milled therefrom to define a fiat cutting edge of width less than approximately .005 inch projecting upwardly from a base portion, said base portion being mounted for movement with an impression cylinder of the press for intermittent engagement with said blanket member to thereby cleanly cut, without embossing, paper passed therebetween.

12. In combination with offset printing press having a blanket member and an impression member adapted to engage paper therebetween, a cutting die secured with said impression member for co-acting with said blanket member to cut such paper as may be passed therebetween comprising, in turn, a homogenous sheet of fully hardened high carbon steel having a portion relieved, as by chemical milling, to define a flat cutting edge of a width less than approximately .005 inch extending generally upwardly of a plate-like base portion towards said blanket member so that passage of such paper between said die and said blanket member forms a single, uniform and clean cut without any embossing thereof.

13. Combination defined in claim 12 wherein said flat cutting edge has a width greater than approximately .001 inch.

14. Cutting die defined in claim 11 wherein said flat edge has a width greater than approximately .001 inch.

15. Cutting die defined in claim 14 wherein said cutting edge is within the range of approximately .015 and .025 of an inch in height above said bases portion.

16. Cutting die defined in claim 15 wherein said base portion is of a thickness within the range of approximately .005 and .010 of an inch.

9 10 17. Cutting die defined in claim 14 wherein said cutting ANDREW R. JUHASZ, Primary Examiner edge defines a closed curve and further comprising elastic material disposed within said closed curve. COAN Assistant Examiner References Cited 5 US. Cl. X.R. UNITED STATES PATENTS 76107; s3 347, 665, 669; 93 ss 168,011 1875 Fry 9358.5 3,022,231 3/1962 Broderick 76-1O7 X 3,142,233 7 9/1964 Downie 93-58 

